The supporting arm for showering is a standard setting of bathroom in some countries, which transversely extends from the vertical wall that has pre-casting pipe, so that the users can mount any kinds of shower assembly according to their needs. Its original idea is to mount a top-down water injection assembly, such as a head shower succinctly mounted to achieve shower function.
In fact, we found that only mounting one head shower is difficult to fulfill multiple demands. For example, the height of the water outlet of the shower supporting arm is not enough so that it cannot fulfill the demands of the tall users; and the function is simple because of the fixing position of the head shower.
Some improvements have been made to solve the problem mentioned above. The common way is to lead out a pipe from the supporting arm and then to connect a head shower in the high position and a handheld shower in the low position of the pipe so that the height of head shower is enough and the shower functions in the low position is diversified. There are some defects in this kind of scheme: firstly, the water pressure is on the low side so that the injection force of the water column generated from the head shower connected to the supporting arm is not enough, wherein the reason is that the cross-sectional area of the head shower's current passage is pressure-relief structure changing from being minor to being major: when the pressure of the current passage is low, the pressure of the injection force of the water column generated from the head shower is accordingly low; using the handheld shower and the head shower simultaneously produces bad spraying effect, because the pressure of the current passage is lower, which makes the injection force generated both from the head and hand shower accordingly lower; secondly, the assembly structure is complicated so that the mounting and using is not convenient; thirdly, the position of the switching valve body is at the end of the supporting arm, and it is too high to handle.